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Paper documents damaged by the tsunami that accompanied the Great East Japan Earthquake have been treated in Iwate Prefecture Museum since April 2011. However, it is difficult to confirm whether the deteriorating factors,such as fungus and bacteria,have been removed from the treated paper documents or not. ATP (adenosine triphosphate)＋ AMP (adenosine monophosphate)swab test method used in food hygiene field is a method for quickly measuring the degree of cleanliness. In order to evaluate the degree of the biological deteriorating factors of paper documents damaged by tsunami, ATP ＋ AMP swab test was applied for research on the tsunamidamaged paper documents in Iwate Prefecture Museum. In addition, microorganisms of dirt, such as soil and sand,which were collected from the paper documents were detected using cultivation. As a result,it was found that the degree of biological deteriorating factors of the paper documents declined after they were treated by removal of dirt with water, sterilization using sodium hypochlorite and dechlorination with water. Although mold growth was observed on dirt collected from an untreated document,there was no mold growth on dirt collected from a document washed with water. The result showed that the conservation method taken in Iwate Prefecture Museum is effective for the sterilization of paper documents damaged by tsunami. Further case studies are required in order to verify the effectiveness of ATP＋AMP swab test method on cultural properties.

In January 2004,excavation of the Kitora Tumulus took place and the relocation of the paintings started. In 2013, the relocation works were completed and the stone chamber of the Kitora Tumlus was buried again. In this report,the results of our surveys of microorganisms detected using cultivation/culture-dependent methods during the period from 2004 to 2013 are summarized,and details of the results of our recent surveys of the stone chamber interior in September 2012 and of the southern stone part of the Tumulus in February 2013 are provided. Soon after people began to go into the stone chamber in 2004,fungal appearances were visible to the naked eye on the wall plaster and murals. In the beginning, fungi such as Trichoderma sp., Penicillium sp., and Fusarium sp. appeared as the major contaminants inside the stone chamber.Ethanol was mainly used to kill and remove such fungal colonies, as it was thought to be one of the mildest of fungicides to the pigments of the murals. In early 2005, small colonies of viscous gels appeared on some parts of the walls. In the summer of 2005,the viscous gels suddenly developed to form biofilms on the plaster walls. In the fall of 2005, small holes (ca. 10mm diam) with black substances inside became obvious on the plaster walls. Such holes might have been caused by the activity of microbes, especially by an acetic acid bacterium,Gluconacetobacter sp. (later identified as G. tumulicola),which had been isolated from one of the black substances from a hole in the ceiling.Dark colored fungi,such as the basidiomycetous fungus Burgoa sp.(later identified as B. anomala) characterized by bulbils and the anamorphic fungi Acremonium (sect. Gliomastix) spp. characterized by darkly pigmented ameroconidia, were also detected inside the stone chamber. In 2008, almost all of the paintings on the side walls and the star charts on the ceiling were relocated. By our survey in 2008, species of the fungal genera Penicillium, Clonostachys, Cladosporium, Phialophora, Ophiostoma, Cylindrocarpon, Phialocephala and Trichoderma were isolated from the samples collected from the stone chamber interior. As some chemicals can be a nutrient source for growth of some microbes, measures such as intermittent UV irradiation were applied from March 2009 to 2013 in order to control microorganisms in the stone chamber interior.Growth of most fungal mycelia was suppressed effectively. However, dark/dematiaceous fungal species of genera such as Acremonium (sect. Gliomastix), Phialophora, Cladophialophora, Arthrinum, and Exophiala were often detected as predominant species. This suggests that those dark fungal species might have been dominant as relatively tolerant species to UV irradiation though significant visible damage by such species was not observed. On the other hand, dark colored fungi, such as Phialophora, Cladophialophora, and Exophiala, were also isolated from the surface of the southern stone of the Tumulus where UV irradiation was not applied. Therefore, direct relationship between UV irradiation and detection of such species is not clear at present. Since Phialophora, Cladophialophora, and Exophiala were often isolated from stone surfaces,they may be considered as fungi that grow on stones.As some of these genera are known to be human pathogens,appropriate precautions are necessary to handle such biofilms in the tumulus environment.

In the Kitora Tumulus,almost all of the paintings on the side walls and the star charts on the ceiling were relocated in 2008, except for those which might have been hidden by a thin layer of mud on the walls. Measures such as intermittent UV irradiation have been applied since March 2009 to control microoraganisms on the plaster. Growth of most fungal mycelia has been suppressed effectively. In the survey of 2010, dematiaceous fungi (e.g.,an anamorphic basidiomycetous fungus Burgoa sp.)were observed,but there was not much problem as a whole. To evaluate the efficacy and influence of intermittent UV irradiation as a control measure against microbial damage of the tumulus, microbiota and microbial activities inside the stone chamber are being examined annually. This paper is a report on the tolerance test of the major microorganisms isolated from the stone chamber interior of the Kitora Tumulus conducted,especially aiming at comparison of UV tolerance between two groups of isolates:isolates before intermittent UV irradiation (2005 to 2007) and isolates during irradiation (2009 to 2011). As bacterial species, isolates of Gluconacetobacter sp.,Stenotrophomonas spp.,Bacillus spp. and actinomycetes were tested. These bacteria were quite susceptible to UV irradiation and totally killed in a few minutes of irradiation in this experiment. No significantdifference was observed in UV susceptibility between the two groups (viz. isolates before and during irradiation, respectively). The anamorphic basidiomycetous fungus Burgoa sp.forms bulbils (superficially similar to small sclerotia),and this structure enables significant tolerance against UV irradiation: the bulbils survived 6 days of UV irradiation. However,this does not mean UV irradiationdoes not have any effect.Since the hypha are sensitive to UV irradiation,it seems that the treatment is effective in preventing the fungus from spreading out. Other fungal isolates, such as Penicillium paneum, Fusarium solani (FSSC clade 3), Acremonium (sect. Gliomastix) murorum, Acremonium (sect. Gliomastix) tumulicola, Cladophialophora sp.and Phialophora sp.,were also tested. Most of the fungal isolates were completely killed by 30 minutes’UV irradiation, but small numbers of spores of some isolates survived 60 minutes of irradiation. However, the survival was 10-4 or 10-5 of the whole spores tested. Therefore, UV irradiation seems very effective as a whole. One Penicillium paneum strain isolated in 2011 showed a bit more tolerance than the strain isolated in 2005. But in the case of Acremonium (sect.Gliomastix)tumulicola, there seemed to be no difference among the two groups of isolates. The dematiaceous fungus Phialophora sp.showed a bit more tolerance than other species tested. As a whole,the two groups of isolates (before and during treatment)did not show significant difference regarding tolerance against UV irradiation in this test. Constant monitoring of microbiota inside the stone chamber and accurate identification with phenotypic and genotypic characterization of the isolates are important to assess intermittent UV irradiation as a control measure for such environment.

A survey was conducted in some historic buildings in Nikko in 2009 using adhesive traps to clarify insect species that cause damage on historic buildings. Some characteristic species of Anobiidae were found as timber pests. Priobium cylingricum was trapped at Sambutsu-do of Rinnohji temple while Trichodesma japonicum and Sculptotheca hilleri were trapped at Daiyu-in Nitenmon. Large-scale survey in historic buildings in Nikko was conducted in 2010. About 27,000 adhesive traps were used for surveys in the loft and basement space of 72 historic wooden buildings. As a result,reality of living conditions of the Anobiids that can harm the buildings in the whole area was revealed. Hadrobregmus pertinax and Oligomerus japonicus, which were not found in the previous year, were also found in 2010. It is assumed that Anobiidae inhabit the entire Nikko area. The distribution of pests in some major buildings have been scrutinized by previous large-scale survey data. As a result, some correspondences have been found with the results of visual survey of damage to building materials. Interesting ecological characteristics of wood-boring beetles were shown from the data, including light attraction. Those data can be useful for future treatments such as fumigation,as well as for restoration and conservation.

In Kitora Tumulus,almost all of the paintings on the side walls and the star charts on the ceiling were relocated in 2008,except for those which might have been hidden by a thin layer of mud on the walls. Measures such as intermittent UV irradiation have been applied since March 2009 to control microoraganisms on the plaster. Growth of most fungal mycelia was suppressed effectively. In the survey of 2010, dark colored fungi such as a black basidiomycetous anamorphic fungus Burgoa sp. were observed, but there was not much problem as a whole. Many species of microorganisms were isolated from six samples from the stone chamber interior at the sampling in October 2011. While the microbiota was almost similar to the ones which had been observed in surveys of the last several years, percentage of the isolates of dark colored fungi seemed higher this year. Gram-negative bacterial species similar to the ones of last year were isolated again. Acetic acid bacteria, Gluconacetobacter spp., which were assumed to be involved in severe deterioration of the plaster,were not isolated in the survey of both 2010 and 2011, after applying intermittent UV irradiation, suggesting that the bacteria are suppressed by the control. However,as a whole,microorganisms seem to survive at places where sufficient UV light does not reach, such as inside cracks of the stones,inside mud layer and inside gels of biofilm,though they do not cause obvious damage.

Microbial contamination on condsolidants of mural paintings is a serious problem. Growth tests of fungal strains isolated from Takamatsuzuka and Kitora Tumuli on resins used for consolidation of mural paintings have been performed before, spraying fungal spores on pure layers of such resins. But growth tests with bacterial or yeast strains could not be designed in the same way as they usually need higher water content. This time, growth of such bacterial and yeast strains was investigated in minimal liquid media which contain each of the consolidants as a major carbon source. As a result, some bacterial strains such as Sphingobium sp., Rhizobium sp., Microbacterium sp., Bacillus thuringiensis, and Stenotrophomonas sp. isolated from Kitora Tumulus and Pseudomonas aeruginosa as a control strain, were able to grow in mediacontaining HPC (hydroxyl propyl cellulose) or MC (methyl cellolose) as a major carbon source. But Gluconacetobacter sp., which was thought to have been involved in severe plaster deterioration in Kitora Tumlus,could not grow in media containing HPC or MC as a single carbon source. Most of the yeast strains tested were not able to grow in media with HPC or MC, either. All the tested microbial species, on the other hand, could grow well in media containing animal glue or funori.

In the Kitora Tumulus, almost all of the paintings on the side walls and the star charts on the ceiling were relocated in 2008, except for those which might have been hidden by a thin layer of mud on the walls. Therefore, controlling measures such as intermittent UV irradiation have been applied since March 2009 to control microoraganisms on the plaster. Intermittent UV irradiation has been performed in the stone chamber of Kitora Tumulus in interval periods between relocation works of the plaster walls without paintings. Growth of most fungal mycelia was suppressed effectively. Dark colored fungi such as a black basidiomycetous fungus Burgoa sp. were sometimes observed, but there was not much problem as a whole. Many species of microorganisms were isolated from nine samples from the stone chamber interior at the sampling in May and October 2010. But the microbiota was almost similar to the ones which we observed in surveys of the last several years. Microorganisms seem to survive at places where sufficient UV light does not reach, such as inside cracks of the stones, inside mud layer, and inside gels of biofilm.

Severe damage was found in some structural wooden pieces of Sambutsu-do in Rinnohji temple, Nikko (World Heritage) during restoration work in 2008. It is extremely important to know the present situation to make a plan for restoration and to propose preventive methods for insect damage. To know the approximate number of insects in the structure, surveys with adhesive traps (fly catcher ribbons) were conducted in 2009 to see adult insect emergence in two historic buildings in the temple. Large-scale survey in historic buildings in Nikko was conducted in 2010 as adhesive traps were proven effective to know the number and species of insects. Priobium cylingricum, Trichodesma japonicum and Sculptotheca hilleri were trapped by adhesive tapes in 2009. About 27,000 adhesive traps were used for surveys in the loft and basement space of 72 historic buildings in 2010. Hadrobregmus pertinax and Oligomerus japonicus, which were not found in the previous year, were also found in 2010. It is not clear how much these anobiid beetles have been involved in the damage to wooden structures. However, since they have been detected, surveys should be conducted to know the levels of damage they have caused. The large-scale survey conducted in 2010 to know the entire condition in Nikko was a great achievement.

The risk of biological deteriorations depends much on the climate and the architectural conditions of buildings which possess cultural properties, books, and documents. The investigation was carried out at the Federal Conservation Center, National Library of Russia, St. Petersburg. Considering the climograph which shows monthly average values of the annual outdoor temperature and relative humidity, there is a lower risk of deterioration by insects and mould in St. Petersburg than in Tokyo. Indoor climate condition of the storage in this library was also far from this risk. However, the range of maximum and minimum values of outside temperature there is quite broad; this may easily cause physical stress to the materials. We performed samplings of surface moulds and air-borne moulds with Cz(Czapek) and MA (Malt extract agar + NaCl 10%) media using an air-sampler (EMD Chemicals Inc,MAS-100). The CFU value inside the storage was always lower than that outside. We detected more xelophilic moulds than hydrophilous moulds inside the storage and found flora with pshycrophilic fungi characteristic in subarctic continental humid climate. Biological damage was not seen during the investigation from April to June, even with high humidity outside. It is possible that the architectural damp course and calorifuge of the traditional style building defend collections from biodeterioration influenced by the outdoor climate.

After Takamatsuzuka Tumulus was excavated in 1972, some materials such as synthetic resins were used for the consolidation of the mural paintings or for the renovation of the adjacent space. Also when the stone chamber was relocated in 2007 to protect the mural paintings from further biodeterioration, some materials for protective facing of the mural paintings had to be chosen for the purpose. At extremely high humidity (approximately 100% RH) of the in situ condition of Takamatsuzuka Tumlus, it is very difficult to keep the site free from microorganisms. There is a possibility that materials used for conservation or renovation in such a condition might be affected more easily than those in usual conditions. We tested the susceptibility of the materials that were used in Takamatsuzuka Tumulus after 1972 or for facing in the 2007 relocation to molds. For this, we used fungal strains for JIS fungal resistance tests for plastics and major fungal strains which were isolated from the tumulus. Paraloid B72, which was used for consolidating the mural paintings in the 1970’s, was found to be susceptible with some fungal strains tested. The resin was more susceptible to fungi when the samples were sprayed with 90% volume ethanol- 10% volume water on the surface, then dried before the test. Epoxy resin, which was used for the renovation of the adjacent space in 2001, was also susceptible to some fungal strains. High molecular weight HPC (hydroxyl propyl cellulose), which was used for facing in 2007, was resistant to fungi. On the other hand, low molecular weight MC (methyl cellulose) 400cps. was susceptible to fungi. Animal glue and funori, which were never used in the Takamatsuzuka stone chamber, were most susceptible to fungi in the same tests. On the whole, synthetic resins tested in this study were not so susceptible as animal glue and funori but showed potential to encourage fungal growth in extremely high relative humidity.

In Takamatsuzuka and Kitora Tumuli, para-formaldehyde fumigation had been used to kill microorganisms. But ethanol or isopropanol was also occasionally used for the removal of colonies of microorganisms which contaminated the murals as dense colonies survived even after para-formaldehyde fumigation. At high concentration, these alcohols are strong disinfectants that do not affect pigments of the mural paintings. Also, para-formaldehyde is presently known as a potent carcinogen, so lower toxic disinfectants were desired for use. However, there was a concern that microorganisms might use such alcohols as carbon sources when the alcohols are diluted to a very low concentration. In order to test this possibility, we examined the growth of strains of microorganisms isolated from Takamatsuzuka and Kitora Tumuli. Strains were cultured in minimum liquid media containing low concentration of each alcohol (approximately 0.5% or 1% in volume) as a single carbon source. All 15 fungal strains tested could utilize ethanol (approximately 0.5% and 1% in volume) as a single carbon source. On the other hand, fungal strains did not utilize isopropanol so effectively as ethanol except for strains of Acremonium (sect Gliomastix) sp. All 5 yeast strains tested could utilize ethanol (approximately 0.5% and 1% in volume). But they did not utilize isopropanol. Nine bacterial strains out of 10 could utilize both ethanol and isopropanol (approximately 0.5% and 1% in volume). Only one strain of Microbacterium sp. did not utilize either of them. Ethanol and isopropanol were supposed to be mild disinfectants to pigments of murals, but when they are diluted to a very low concentration, they might act as carbon sources, ie. nutrients for microorganisms.

The feasibility of drill resistance method using RESISTGRAPH apparatus to evaluate insect attack in wooden structural members of historic buildings was investigated. Based on the results presented in a previous report, the drill resistance method was applied to the posts of Sambutsudo of Rinnohji. It was revealed that characteristic patterns of the change in drill resistance were obtained, both for the sound part of the posts and the part attacked by insects. The results and their interpretation discussed are supported by the results of visual inspection of the posts. Although it takes relatively more time and cost, the distribution of insect attack can be clarified by applying this method to the entire structure of a building.

A very rare anobiid species in Japan, Priobium cylindricum, was found by chance in the restoration work of the Sambutsu-do of Rinnohji temple in 2008. The insect caused very severe damage in hard (heart) wood. The inside of beams, pillars and smaller wooden pieces was extensively damaged to a powdery state. However, damage was not clear by observation from the outside of the structure, especially when seen from the red painted thick layer of urushi. Such damage was more obvious in the recycled older wooden pieces, which suggested a possibility of the survival of the insects in the recycled wood. Records of previous restoration were examined, especially with photos of the restoration made from 1954 to 1961. Extensive damage was seen at the restoration at that time. The damage seen in the records and photos seemed to have characteristics similar to the recent damage by Priobium cylindricum. From the comparison of the characteristics of damage, it was suggested that Priobium cylindricum might have been involved in the similar damage to the building at the time of restoration several decades ago.

The feasibility of drill resistance method using Resistgraph F-300S (IML-Instrumenta Mechanik Labor System GmbH) apparatus to evaluate the insect attack in wooden structural members of historic buildings was investigated. It was revealed that the drill resistance changed characteristically at the position of the holes bored by insects. However the resistance is influenced also by annual ring structure of wood and the resistance changed drastically by the drill direction to annual ring structure. The method is not completely non-destructive, however the hole made by the drill is about 3mm in diameter and has no influence on the strength of the structural members of the buildings in ordinal cases.

Damage by wood borer insects is often observed on wooden objects or wooden historic buildings. When we guess levels of damage inside the wooden objects, holes on the surface of wood or powders from the holes are important clues in accessing damage by observation. Sometimes “active” infestation is strongly suggested by the emergence of insects from the wooden holes, or by continuous production of wooden powders including insect frass and droppings. Though such observation is important, methods to observe the inside of objects would also be very effective in estimating the level of damage. X-ray CT (computer tomography) scanning is one of such non-destructive methods to look into conditions inside cultural objects. Inthis study, we were able to obtain very good images of insects and the damaged parts inside the wooden objects. First, as a preliminary test, larvae of a dermestid (Attagenus japonicus) or their casting skins were put into two wooden pieces respectively. Consequently, only larvae were detected very clearly by CT in the wooden piece, but casting skins showed no significant signal. This suggested that active larvae (or insect bodies in similar condition) can be detected by CT probably owing to differences in density. Then we observed the damaged structural wooden pieces from Rinnohji temple of Nikko (World Heritage) infested by a rare kind of anobiid, Priobium cylindricum. As a result, insects were detected inside the pieces very clearly. Also clear images of damaged parts inside the wooden pieces were shown. Such information would be important to know the characteristics of damage by the rare insect species, about which we do not have enough information for now.

Since the use of methyl bromide was banned at the end of 2004, various alternative methods have been adopted in the museum community in Japan. Such methods include non-chemical methods to eradicate insects, and some other kinds of fumigants. There have been many consultations on unsatisfactory results of efficacy, inquiries about usage of chemicals, and questions about concerns on human health from the museum community in these four years. From these situations, we thought it very important to know recent possible problems related to the use of various kinds of pest controlling methods in museums. Simple inquiry sheets were delivered to about 340 museum staff in Japan from July to September, 2008. The inquiry sheets consist of three categories of questions: (1) unsatisfactory efficacy, (2) concerns on human health, and (3) effects on objects or portable fittings. About 55 percent of the sheets (185 answers) were sent back. The results clearly showed possible problems or difficulties on some pest controlling agents at present. The information is very important in improving the methodologies of pest control in museum communities in Japan.

Restoration work of the Sanbutsu-do of Rinnohji temple in Nikko (World Heritage) was conducted in 2008. Severe damage was found in some structural wooden pieces of the temple. The damage seemed to have rare characteristics: very severe damage in hard (heart) wood, such parts were extensively damaged to powdery state and there were many holes of various sizes. However, damage was not clear by observation from outside of the structure, especially when seen from the red painted layer of Urushi. Such characteristics were very rare, though many examples of insect damage have been observed in historic structures in Japan. Thus, the severely infested wooden pieces were investigated to identify the insects involved. Insects found in one of the pieces were identified as Priobium cylindricum, a very rare anobiid species in Japan. This is thought to be the first record of damage by this species in a historic building of important cultural property in Japan. Sanbutsu-do was reconstructed in 1645 (Edo period). The damage was more severe in parts where old wooden pieces (Edo period) are used than in the partially added pieces dating to the 1950's restoration. Damage was observed at various parts of the structure. Countermeasures were proposed based on the results of the survey of the structure.

Microbiological deterioration is one of the major causes of the foxing formation. We observed the fluorescence of foxing spots on a series of Japanese paper made in the early Showa period. Brown spots were coincident with fluoresce spots, but the area of fluoresce spots were bigger than that of brown spots under irradiation of black light. We isolated Aspergillus penicilloides from the foxing spot with DG18 plates, and inoculated the fungal strain on sterilized paper (Watman and Japanese kozo paper). Aspergillus penicilloides, which has colorless hyphae, non-brown spores and non-brown metabolite was grown on these paper in 25℃ and Aw 0.85 in two months. These spots fluoresced under the irradiation of black light but were not brown. These facts may show that these foxing spots were not brown at the early stage of the growth of the fungi. On the other hand, Eurotium herbariorum, considered as one of fungi which cause foxing, makes brown hyphae and yellow ascocarps in the same conditions. It is necessary to clarify the conditions that make browning reaction with non-brown fungal body and metabolite of Aspergillus penicilloides.

In January 2004, excavation of the Kitora Tumulus took place and the relocation of the paintings started. However, after people began to go into the tumulus, we started to see fungal growth. In the beginning, fungi such as Trichoderma sp., Penicillium sp. and Fusarium sp. were seen inside the tumulus. Ethanol was mainly used to kill and remove such fungal colonies, as it was thought to be one of the mildest of fungicides with respect to the pigments used in the murals. In early 2005, small colonies of viscous gel appeared on some parts of the walls. In the summer of 2005, the viscous gels (biofilms) suddenly developed to form biofilms on the plaster walls. In the fall of 2005, small holes with black substances inside became obvious on the plasterwalls; the holes seemed to have developed from the back side of the plaster. Such holes might have been caused by the activity of microbes, especially by an acetic acid bacterium, Gluconacetobacter sp. The acetic acid bacterium had been isolated from one of the black substance from a hole of the ceiling. In 2008, almost all of the paintings on the side walls and the star charts on the ceiling were relocated, except for those which might have been hidden by a thin layer of mud on the walls. By a survey in June 2008, species of the fungal genera Penicillium, Clonostachys, Cladosporium, Phialophora, Ophiostoma, Cylindrocarpon, Phialocephala and Trichoderma were isolated from the eight gel samples from the interior of the stone chamber. But the basidiomycetous fungus Burgoa sp. and the anamorphic fungus Acremonium (sect. Gliomastix) sp. were not isolated this time. An acetic acid bacterium, Gluconacetobacter sp., was isolated from three samples out of eight, which suggested that this bacterium might spread to various parts of thestone chamber's interior. As this bacterium was shown to decompose CaCO3, there is strong concern on its effect on the plaster. Chemicals to treat microbes in Kitora Tumulus has been selected from consideration of their efficacy on microbes, possible adverse effects on paintings and toxicity to human. Mainly, ethanol, isopropanol, formalin and isothiazolones (KathonTM CG) have been used depending on conditions of the plaster or the stones and purposes. Selection and the way of using the chemicals must be carefully designed in line with the timing of further relocation of the plaster. Some chemicals might be a carbon source to encourage growth of some microbes or secretion of acids by them. Special caution to such side effects is necessary.

A possibility of insect damage became obvious in a historic house, Hyuga-bettei, in Atami city, Shizuoka prefecture. The structure had been designated as an important cultural property. It has a beautiful underground structure designed by a German architect, Bruno Tauto, and it is built on a steep cliff facing the Pacific Ocean. In a hall in the underground structure, paulownia and bamboo are used for the delicate decorations on the walls. But from the early summer of 2006, the staff noticed manysmall holes on such wooden parts and powder coming out from these holes. In August 2006, we did an inspection of the damage. Several dead adult insects of a book borer anobiid Gastrallus sp. were found with the powder from the insect holes. The damage seemed active as such powder was continuously coming out. We conducted surveys of the whole structure and found an old wooden phonograph surrounded by dead insects in a storage adjacent to the hall. The wooden phonograph was significantly infested by Gastrallus sp. It had also rotten in humid condition. As it was placed just on the backside wall of the heavily infested wall in the hall, it might have been a cause of infestation of the wooden parts of the hall and other chambers. Removal of the wooden phonograph and extensive cleaning and ventilation in the storage was advised. Also fumigation or residual insecticide treatments to the infested parts was necessary. The book borer anobiid Gastrallus sp. is a very common insect pest of books in Japan, but few examples are known in which they have infested wooden objects. So we report this example as a rare case of such infestation.

Takamatsuzuka Tumulus was excavated in 1972, and the policy of conservation of its beautiful plaster paintings was discussed intensely at that time. Specialists in the conservation of historical sites made of stone were invited from France and Italy. Though there was a suggestion to relocate the plaster paintings by a method like the storappo method used with fresco, there was also a great concern about the stability of the plaster paintings which had been kept in high humidity of about 100% RH for more than a thousand years. The plaster of the mural paintings had deteriorated significantly at the time of the excavation in 1972; exfoliation and flaking were seen at many places on the paintings. Considering such conditions, it was thought thatdesiccation would be catastrophic to the beauty and stability of the plaster paintings. It was also feared that storappo of such heterolytic plaster surfaces would be very difficult. Thus it was determined to maintain the plaster paintings on site, in very high humidity. The basic concept of this decision was to keep the plaster paintings in the original environment, hopefully in the environment of unexcavated, buried condition. High humidity was good for the physical condition of the plaster, but at the same time it imposed a very difficult situation on fighting biodeterioration of the paintings. None of the methods of control by chemicals, low oxygen atmosphere, very low temperature, etc. was realistic in this case. Keeping the plaster paintings in about 100% RH means relying mainly upon the natural balance of microorganisms in a closed environment. When a small system is shut out from the outside world, microorganisms such as fungi and bacteria would be active at the start, but gradually come to a balancing point of no drastic change. However every small perturbation of temperature, humidity, invasion of new kinds of microorganisms from outside, or change by restoration works would break the balance and cause a new outbreak of microorganisms. Thus the strategy for maintaining the paintings should be to keep any stimulations out from the stone chamber, to keep the original buried environment. A facility was constructed to maintain the temperature and humidity of the adjacent space the same with those in the soil when staff had to go into the stone chamber. Thorough disinfection has also been performed on mechanics and staff when restoration works or annual checking were necessary. More than thirty years have passed since the decision was made. Although great efforts have been made to keep the paintings free from outbreak of microorganisms, changes in the condition that occurred a few times have caused fungal outbreaks on the plaster paintings. Once such an outbreak occurred, fungi deteriorated the plaster paintings significantly both esthetically and physically. Such deterioration has accumulated to a very dangerous point for keeping the paintings in the present condition. Now it is considered time to make drastic decisions for the conservation and restoration of the paintings to protect them from further deterioration.

To study how to maintain burial mounds, a questionnaire survey was conducted on conservation problems at burial mounds in Fukuoka, Kumamoto, Oh-ita, and Nagasaki, prefectures. The rate of return was 68.8% (January 2004) in Fukuoka and 62.5% (May 2005) in Kumamoto. Boards of education of 53 cities in Fukuoka administrate approximately 130 burial mounds; boards of education of 15 cities in Kumamoto administrate approximately 142 mounds. It was found that biodeterioration had occurred in 10% of the mounds. Overgrowth of lichen is a serious problem for the conservation of mounds which are open without any interception of light. Floods and water leakage into chambers from cracks of mounds made by invasion of plant roots are serious threats to the maintainance of the mounds. It was also mentioned in many of the comments that the collapse of trees on the mounds occurred often due to heavy rain and big typhoons and that the boards of educations are always financially distressed. Molds were recognized in some chambers and it was also pointed out that mold growth was suppressed after partition by glass with sealing. Many boards of education also hoped that specific instructions to maintain mounds - for example, how the mounds should be remade, what their ideal structures and thicknessare, which plants should be used to cover the mounds, and so on - be proposed as standard.

Although environmental and sanitary engineers are aware of the importance of microbial activity, many civil and architectural engineers do not appreciate the part microbiological processes play in, for example, biodeterioration of concrete and other construction materials. Microbes promote also weathering of rock to soils and swelling of soils, clogging of boreholes and irrigation systems, and biofouling in embankment dams. Microbes promote the biodeterioration by their enzymes. The paper involves the biodeterioration of concrete structures. In order to help understanding of its process, a complex dynamic ecosystems model on biodeterioration of concrete structures is presented. In order to understand the alteration by biodeterioration, total carbon (TC) and total nitrogen (TN) of test piece of fresh concrete and of various deteriorated concrete structures were measured with C-N analyzer. Observations of microbial activity on the surfaces of deteriorated concrete structures were also conducted by using digital microscope. Finally, the Importance of biology, especially, of microbiology and ecology in civil engineering is emphasized.

Although environmental and sanitary engineers are aware of the importance of microbial activity, many civil and architectural engineers do not appreciate the part microbiological processes play in, for example, biodeterioration of concrete and other construction materials. Microbes promote also weathering of rock to soils and swelling of soils, clogging of boreholes and irrigation systems, and biofouling in embankment dams. Microbes promote the biodeterioration by their enzymes. The paper involves the biodeterioration of concrete structures. In order to help understanding of its process, a complex dynamic ecosystems model on biodeterioration of concrete structures is presented. In order to understand the alteration by biodeterioration, total carbon (TC) and total nitrogen (TN) of test piece of fresh concrete and of various deteriorated concrete structures were measured with C-N analyzer. Observations of microbial activity on the surfaces of deteriorated concrete structures were also conducted by using digital microscope. Finally, the Importance of biology, especially, of microbiology and ecology in civil engineering is emphasized.